Technical Field
The present disclosure relates to an adjusting device for adjusting a yaw position of a nacelle of a wind turbine, and it relates to an adjusting means for use in such an adjusting device. Furthermore, the disclosure relates to a wind turbine having an adjusting device for adjusting a yaw position of the nacelle, and it relates to a method for adjusting a yaw position of a nacelle.
Description of the Related Art
Adjusting devices for adjusting the yaw position of a nacelle of a wind turbine are known. For this purpose, many standard devices use a plurality of adjusting drives, which engage in a ring gear by means of a pinion and can thereby provide the yaw adjustment. Following attainment of a new yaw position, the latter can be fixed in that the drives are stopped and partially tensioned against each other in order thereby also to preclude any problems of a gear clearance between the pinion and ring gear. In this case, there may be the problems of wear between the drive pinion and the ring gear, and of the work required, and the fault susceptibility, in proving lubrication here.
Hydraulic systems are also known, such as, for example, from the international application WO2010/029210. The latter describes a hydraulic system that comprises a plurality of hydraulic units, which each have a cylinder piston having a brake shoe system. The brake shoe system grips on a flange, in order basically to fix this brake shoe system there, in order then to actuate the hydraulics, and thereby move this brake disc ring and a nacelle that is connected thereto. The reliability of the yaw adjustment and, moreover, also holding of the nacelle in a selected yaw position also depends substantially on the quality, at least functional capability, of this brake shoe system.
The document EP0952337 B1 likewise relates to a hydraulic system, in which a plurality of force transmission elements act on a ring gear, against which they are pressed from the inside. Accordingly, similar problems may occur here in connection with the ring gear and the counter-elements acting thereon, as in the case of the yaw adjustment described above, by means of pinions and a matched ring gear. Moreover, the solution of this latter document requires both an actuator for pressing the force transmission element against the ring gear, and for exerting the actual movement. Insofar as any tensile force at all can also be exerted upon the ring gear, such a tensile force, however, acts against the pressing force with which the force transmission element is pressed against the ring gear.
Consequently, in this case problems of the hydraulic drives are unnecessarily combined with the problems of the use of a ring gear.